PUBLICATION

Novel intronic microRNA represses zebrafish myf5 promoter activity through silencing dickkopf-3 gene

Authors
Hsu, R.J., Lin, C.Y., Hoi, H.S., Zheng, S.K., Lin, C.C., and Tsai, H.J.
ID
ZDB-PUB-100322-10
Date
2010
Source
Nucleic acids research   38(13): 4384-4393 (Journal)
Registered Authors
Tsai, Huai-Jen
Keywords
none
MeSH Terms
  • Animals
  • Gene Knockdown Techniques
  • Gene Silencing*
  • Introns*
  • MicroRNAs/antagonists & inhibitors
  • MicroRNAs/genetics
  • MicroRNAs/metabolism*
  • Myogenic Regulatory Factor 5/genetics*
  • Myogenic Regulatory Factor 5/metabolism
  • Promoter Regions, Genetic
  • Protein Biosynthesis
  • Protein Isoforms/genetics
  • RNA, Messenger/metabolism
  • Somites/metabolism
  • Zebrafish/genetics*
  • Zebrafish/metabolism
  • Zebrafish Proteins/genetics*
  • Zebrafish Proteins/metabolism
PubMed
20236986 Full text @ Nucleic Acids Res.
Abstract
A strong, negative cis-element located at the first intron +502/+835 (I300) of zebrafish myf5 has been reported. To elucidate the molecular mechanism underlying this repression network, we microinjected zebrafish single-cell embryos with I300 RNA, resulting in the dramatic reduction of luciferase activity driven by the myf5 promoter. Within this I300 segment, we identified an intronic microRNA (miR-In300) located at +609/+632 and found that it was more highly expressed in the older mature somites than those newly formed, which negatively correlated with the distribution of zebrafish myf5 transcripts. We proved that miR-In300 suppressed the transcription of myf5 through abolishing myf5 promoter activity, and we subsequently identified the long isoform of the Dickkopf-3 gene (dkk3) as the target gene of miR-In300. We further found that injection of the dkk3-morpholinos (MOs) resulted in downregulation of myf5 transcripts in somites, whereas co-injection of myf5 mRNA with dkk3-MO1 enabled rescue of the defects induced by dkk3-MO1 alone. Finally, injection of miR-In300-MO enhanced both myf5 transcripts in somites and the level of Dkk3 protein in zebrafish embryos. Based on these findings, we concluded that miR-In300 binds to its target gene dkk3, which inhibits the translation of dkk3 mRNA and, in turn, suppresses zebrafish myf5 promoter activity.
Genes / Markers
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Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping